In my analysis for r56076 I missed the case where the original
multiplication overflows.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56082 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 8f57820..46ac762 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -5789,7 +5789,8 @@
// e.g. X/-5 op -3 --> [15, 20)
LoBound = Prod;
LoOverflow = HiOverflow = ProdOV ? 1 : 0;
- HiOverflow = SubWithOverflow(HiBound, Prod, DivRHS, true);
+ if (!HiOverflow)
+ HiOverflow = SubWithOverflow(HiBound, Prod, DivRHS, true);
}
// Dividing by a negative swaps the condition. LT <-> GT